[clang] [llvm] [PowerPC][AIX] Support #pragma comment copyright for AIX (PR #178184)

[Sean Perry via cfe-commits]

================
@@ -3284,27 +3289,53 @@ void PragmaCommentHandler::HandlePragma(Preprocessor &PP,
     return;
   }
 
-  // Verify that this is one of the 5 explicitly listed options.
+  // Verify that this is one of the 6 explicitly listed options.
   IdentifierInfo *II = Tok.getIdentifierInfo();
   PragmaMSCommentKind Kind =
-    llvm::StringSwitch<PragmaMSCommentKind>(II->getName())
-    .Case("linker",   PCK_Linker)
-    .Case("lib",      PCK_Lib)
-    .Case("compiler", PCK_Compiler)
-    .Case("exestr",   PCK_ExeStr)
-    .Case("user",     PCK_User)
-    .Default(PCK_Unknown);
+      llvm::StringSwitch<PragmaMSCommentKind>(II->getName())
+          .Case("linker", PCK_Linker)
+          .Case("lib", PCK_Lib)
+          .Case("compiler", PCK_Compiler)
+          .Case("exestr", PCK_ExeStr)
+          .Case("user", PCK_User)
+          .Case("copyright", PCK_Copyright)
+          .Default(PCK_Unknown);
+
   if (Kind == PCK_Unknown) {
     PP.Diag(Tok.getLocation(), diag::err_pragma_comment_unknown_kind);
     return;
   }
 
+  if (PP.getTargetInfo().getTriple().isOSAIX() && (Kind != PCK_Copyright)) {
+    // On AIX, pragma comment linker, lib, compiler, exestr and user are
+    // ignored.
+    PP.Diag(Tok.getLocation(), diag::warn_pragma_comment_ignored)
+        << II->getName();
+    return;
+  }
+
   if (PP.getTargetInfo().getTriple().isOSBinFormatELF() && Kind != PCK_Lib) {
     PP.Diag(Tok.getLocation(), diag::warn_pragma_comment_ignored)
         << II->getName();
     return;
   }
 
+  if (Kind == PCK_Copyright) {
+    if (!PP.getTargetInfo().getTriple().isOSAIX()) {
+      // Restrict pragma comment copyright to AIX targets only.
+      PP.Diag(Tok.getLocation(),
----------------
perry-ca wrote:

Why did you create a new message for this case instead of using `warn_pragma_comment_ignored` like in the other cases for pragma being ignored?  I'd use the same message for all of these cases.

https://github.com/llvm/llvm-project/pull/178184